Alternate Names: Velva Cast
A large particle size kaolin intended for casting slips. It is low in plasticity and fires a darker color than what the reported iron would indicate? Combining some of this material with other kaolins of finer particle size in casting recipes will reduce casting times because of the greater permeability of the slip.
Kaolins of this type are also valuable for use in tuning the shrinkage and plasticity of slips or engobe applied to wet, leather hard or dry ware (as opposed to using more expensive calcined kaolins). Because their shrinkage is very low, they can be substituted for part of the regular kaolin and there will be minimal impact on the fired properties.
Pure clay mineral, there are many brand names of varying purity and iron content.
|Pyrometric Cone Equivalent||34-36|